Did you know there’s a hormone that not only manages your appetite and satiety but also directly influences your thyroid and other hormones in the body? Let me introduce… Leptin! As well as a dysfunction called leptin resistance that might be one of the reasons your weight is not shifting and your thryoid hormones are suboptimal despite medication.
Ok, so Leptin is mainly known as the hunger hormone as it plays a huge role in your appetite control and metabolism. It communicates with your brain to let you know when you’re full, and helps regulate how your body uses energy. However, when your body becomes resistant to leptin, this balance is thrown off, leading to a series of metabolic issues, including problems with your thyroid.
Let’s dive into how leptin resistance can mess with your thyroid and other hormones, and what you can do about it.
What is Leptin Resistance?
Leptin resistance happens when your body stops responding properly to leptin signals, even when leptin levels are high. This happens when we have excess weight, where there’s a lot of fat tissue producing a lot of leptin. Over time, the brain, particularly the hypothalamus, gets desensitised to leptin. As a result, you feel hungrier, your metabolism slows down, and you gain more weight. It’s a tough cycle to break. The reality is, if you have any excess weight, and you suspect insulin imbalances, leptin resistance is likely the cause.
Leptin and Thyroid Function
Your thyroid gland, which produces hormones like T3 (triiodothyronine) and T4 (thyroxine), is key for managing metabolism. Leptin affects the hypothalamus-pituitary-thyroid (HPT) axis, a crucial pathway for keeping thyroid hormones in check. When Leptin resistance kicks in, this signalling process can get disrupted, leading to problems with thyroid hormone production.
How Leptin Resistance Affects Thyroid Function
- Messed Up TRH and TSH Levels: Leptin resistance can impair the release of TRH from the hypothalamus, leading to lower TSH levels from the pituitary gland. This means less stimulation for your thyroid to produce T3 and T4, resulting in lower thyroid hormone levels.
- Slowed metabolism: Thyroid hormones are essential for keeping your metabolism running smoothly. When their levels drop due to leptin resistance, you might experience weight gain, fatigue, feeling cold all the time, and even depression.
- The vicious cycle of excess weight and thyroid Issues: This relationship is a two-way street. Leptin resistance can cause hypothyroid-like symptoms, and having hypothyroidism can make you gain more weight, increasing leptin levels and worsening leptin resistance. It’s a challenging cycle to break.
Leptin’s Impact on Other Hormones
Leptin doesn’t just affect the thyroid. It also plays a role in regulating other hormones:
Insulin: Leptin can influence insulin sensitivity. Leptin resistance is often associated with insulin resistance, which can lead to type 2 diabetes.
Cortisol: Leptin interacts with the hypothalamic-pituitary-adrenal (HPA) axis, influencing cortisol production. Leptin resistance can lead to imbalances in cortisol levels, which affects stress response and metabolism.
Sex hormones: Leptin plays a role in the regulation of reproductive hormones, including estrogen, progesterone, and testosterone. It can also affect fertility and your chances of successful conception!
What are some of the signs and symptoms of leptin resistance?
Some of the key symptoms of leptin resistance include persistent hunger and cravings, not feeling satisfied after meals and craving sweet foods! Interestingly it can also show up as no hunger first thing in the morning. Leptin resistance makes weight loss really hard, especially combined with insulin resistance, and can lead to weight gain with a seemingly normal calorie intake.
“How do we fix this, Aggie?” you may ask. As with everything else, it requires a balanced approach.
Leptin operates on a circadian clock and this is where the healing must start. Leptin docks to the hypothalamus when we’re asleep, and a disrupted sleep pattern and insufficient melatonin levels will get in the way of this process. Exposure to morning light, and mid-day sun and making sure you wear blue light-blocking glasses after sunset is absolutely key!
Another good place to start is paying attention to the meal timing, leaving at least 2-3 hours between your last meal and sleep time, and eating within an hour of waking up.
Reversing leptin resistance includes balancing your other hormones like cortisol and insulin, as when it comes to your metabolic health, nothing works in isolation! But trust me, leptin is by far the most important piece of the weight loss and thyroid health equation and it’s absolutely possible to reverse it!
So, if you’re reading this thinking, “This is me! I’m ready to take action and help my body find balance, but I need support.”
I’ve got you.
Join me in UNDIET, where I will teach you all about optimising your hormones (leptin, insulin, cortisol) for sustainable weight loss without another diet. And as usual, if you have any questions, please get in touch!